routeros-scripts/dhcp-to-dns
2018-11-09 21:32:01 +01:00

76 lines
2.6 KiB
Text

#!rsc
# RouterOS script: dhcp-to-dns
# Copyright (c) 2013-2018 Christian Hesse <mail@eworm.de>
#
# check DHCP leases and add/remove/update DNS entries
:global "identity";
:global "domain";
:global "hostname-in-zone";
:local zone;
:if ($"hostname-in-zone" = true) do={
:set zone ("dhcp." . $identity . "." . $domain);
} else={
:set zone ("dhcp." . $domain);
}
:local ttl "00:05:00";
:local hostname;
:local fqdn;
:local dnsip;
:local dhcpip;
:local dnsnode;
:local dhcpnode;
:foreach static in=[ / ip dns static find where name ~ (".*\\." . $zone) ] do={
:set fqdn [ / ip dns static get $static name ];
:set hostname [ :pick $fqdn 0 ( [ :len $fqdn ] - ( [ :len $zone ] + 1 ) ) ];
:set dhcpnode [ / ip dhcp-server lease find where host-name=$hostname dynamic=yes ];
:if ( [ :len $dhcpnode ] > 0) do={
:log debug ("Lease for " . $hostname . " still exists. Not deleting.");
} else={
:local found false;
:log info ("Lease expired for " . $hostname . ", deleting DNS entry.");
/ ip dns static remove $static;
}
}
:foreach lease in=[ / ip dhcp-server lease find where dynamic=yes ] do={
:local mac [ / ip dhcp-server lease get $lease mac-address ];
:set dhcpip [ / ip dhcp-server lease get $lease address ];
:local comment ("managed by dhcp-to-dns for " . $mac);
:set hostname [ / ip dhcp-server lease get $lease host-name ];
:while ($hostname ~ " ") do={
:local pos [ :find $hostname " " ];
:set hostname ( [ :pick $hostname 0 $pos ] . [ :pick $hostname ($pos + 1) 999 ] );
};
:if ( [ :len $hostname ] > 0) do={
:set fqdn ( $hostname . "." . $zone );
:set dnsnode [ / ip dns static find where name=$fqdn ];
:if ( [ :len $dnsnode ] > 0 ) do={
:set dnsip [ / ip dns static get $dnsnode address ];
:local leases [ / ip dhcp-server lease find where host-name=$hostname dynamic=yes ];
:local hostnamecount [ / ip dhcp-server lease print count-only where host-name=$hostname dynamic=yes ];
:if ( $hostnamecount > 1) do={
:foreach j,lease in=$leases do={
:if ($j + 1 = $hostnamecount) do={
:set dhcpip [ / ip dhcp-server lease get $lease address ];
}
}
}
:if ( $dnsip = $dhcpip ) do={
:log debug ("DNS entry for " . $fqdn . " does not need updating.");
} else={
:log info ("Replacing DNS entry for " . $fqdn . ", new address is " . $dhcpip . ".");
/ ip dns static set name=$fqdn address=$dhcpip ttl=$ttl comment=$comment $dnsnode;
}
} else={
:log info ("Adding new DNS entry for " . $fqdn . ", address is " . $dhcpip . ".");
/ ip dns static add name=$fqdn address=$dhcpip ttl=$ttl comment=$comment;
}
}
}